/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.hadoop.hive.ql.exec;

import org.apache.hadoop.hive.ql.metadata.HiveException;
import org.apache.hadoop.hive.ql.plan.ExprNodeNullDesc;
import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspector;
import org.apache.hadoop.hive.serde2.objectinspector.primitive.PrimitiveObjectInspectorFactory;

// This function will not be used currently, since the function expressions
// change the void to the first matching argument
/**
 * ExprNodeNullEvaluator.
 *
 */
public class ExprNodeNullEvaluator extends ExprNodeEvaluator<ExprNodeNullDesc> {

  public ExprNodeNullEvaluator(ExprNodeNullDesc expr) {
    super(expr);
  }

  @Override
  public ObjectInspector initialize(ObjectInspector rowInspector) throws HiveException {
    return outputOI = PrimitiveObjectInspectorFactory.writableVoidObjectInspector;
  }

  @Override
  protected Object _evaluate(Object row, int version) throws HiveException {
    return null;
  }
}
